Smoking rates in NSW have dropped by more than seven per cent over 15 years, according to data released on World No Tobacco Day.
The NSW Population Health Survey reveals 15.2 per cent of adults were smokers in 2017, compared to 22.5 per cent in 2002.
The data shows more than half of the adults in the state have never taken up smoking.
Chief Health Officer Dr Kerry Chant said the decline in smoking rates was across population groups, including youth and Aboriginal people.
"We need to be vigilant to ensure that smoking rates continue to decrease, as there has been a stabilisation of rates in recent years," Dr Chant said in a statement.
The survey also shows the number of pregnant women who smoke has nearly halved from 16.3 per cent in 2002 to 8.3 per cent in 2016.